The present invention is directed to an automatic packaging machine having individual controlled atmosphere chambers for each package movable along a conveyor and more specifically to controlled atmosphere chamber means comprised of a plurality of package receiving base members movable along a first closed path conveyor and a plurality of covers connected to a common atmosphere controlling means movable along a second closed path partially overlapping the first closed path for sealing engagement with the base members.
It is well known from industrial practice, technical magazines and international patent literature that various packaging machines are provided with means for controlling the atmosphere completely or partially during the package filling and sealing operation. In such machines, the empty bags are transferred from a forming station to a filling conveyor and subsequent to being filled, the bags are transferred into a chamber which is then sealed. The interior of the sealed chamber is then subjecting to a vacuum or other controlled atmosphere depending upon the nature of the packaging operation.
During the transfer of the bags from the forming stations to the filling stations and from there to the controlled atmosphere chambers, numerous disadvantages can arise which would restrict the efficiency of the entire packaging process. There is always the possibility of mishandling the bag during the numerous transfers with the possible consequent spilling of the content of the bag before the bag can be sealed. The frequent transferring of the bag also leads to the possibility of the bunching up of the bags or a jamming of the bags on the various conveyors utilized in the multiple transfer operation.